Setts



F. H; c. coPPus.

FAN BLOWER.

AAPPLIL`.A\1 |0N FILED SEPT. l5, |914.

Ffa/a y@ Ptented July s', 1919.--

UNITED sTATEs PATENT oFFIoE.

FRANS H. C. COPPUS,.OF WORCESTER, MASSACHUSETTS, ASSIG-NOR TO COPPUS ENGINEERING AND EQUIPMENT COMPANY, OF WORCESTER, MASSACHU- SETTS, A CORPORATION 0F MASSACHUSETTS.

FAN-BLOWER.

Speeication of Letters Patent.

Patented July s, 1919.

Application mea september 15, 1914. semi No. 861,907.

T0 all lwhom t may concern:

v B e' it known that I, FRANs H. C. Corpus, a citlzen of the United States, residingl at Worcester, -in the county of Worcester and Commonwealth of Massachusetts, have invented a new and useful Improvement in.

' ing an artificial draft, as, for instance, in

of a steam turbine 4,'whioh is located at a 'maintaining a pressure in the ash pit of a boiler. One of the objects of the invention 1s to lncrease the efficiency of devices of this class; the construction and arrangement of parts, by means of -which the above and other objects are attained, are set yforth in the followmg description and illustrated in the accompanying drawings, in which- Figure 1 is a side elevation, partly in cen-- tral longitudinal section, of my improved` apparatus, and

Fig. 2 is an end view of the casing or hood l for the fan blower, the latter being removed for the sake of clearness.

Similar reference characters refer to similar parts in both figures.

In carrying my invention into effect, I provide a fan 1, of any well known type, disposed within the open end or mouth 2 of a casing or hood 3, which'forms a conduit for the air set in motion by the'fan. vAnywell known means may be employed to impart rotation to the fan 1; in the present instance I have shown said fan mounted on the shaft suitable distancefrom the mouth 2 of the hood 3 to permit the free passage of air to the blades of said fan.

. It has been the general practice, heretoffore, t0 make the internal diameter of the hood substantially uniform in the vicinity of the fan, with the result that a portion of the air, thrown centrifugally outward by the blades of the fan, impinges against the wall of said hood, in substantially radial directions. As a consequence, a portion of the air leaks backwardly toward the mouth of the hood and, furthermore, there vis a considerable pressure loss due to the'choking effects and eddy currents caused by the impact of the air against the casing.

My invention contemplates a gradual change in the direction of that portion of stray ystream issuing ina general] diameter of the hood, and immediately surrounding the fan 1.- The forward portions of the blades of said fan project beyond the forward edge of said flange, as shown clearly in Fig. 1. Said I'iange edge may, if desired, be beveled, as shown at 6, to assist the action of the flange 5 in imparting to the air thrown outwardly by said blades a gradual change in direction before said air comes in contact with the walls of the hood proper.

4-In consequence of the expansion of the .hood 'or casing at the point where the fan 1s located, thedirect radial impingement of the air against the walls of the hood -is avoided, and the losses due to the backward leaking of the air, and to the formation of eddy currents, are largely eliminated. A portion of` `the annular space 7 formed between the walls of the hood 3 and the lip 5 is preferably partitioned ofl by the walls 8, Fig. 2, to form a passage 9 into which the exhaust steam from the turbine 4 is delivered by means of the pipe 10. The entrance 'of said steam to the hood 3 in an axial directionfurther assists in imparting to the air a proper course lengthwlse of the. hood.

1. An air propelling device, comprislng a fixed casing having an opening, a rotatable blower having vanes fitting closely in the plane of the opening creating a current of air composed of several components, one a main stream and another a stray stream tending to exert a choking effect between the vanes and the walls of the opening, and means for relieving the choking effect of the stray stream and for directing said stray stream into substantially the same path as the main stream, the casing being constructed to confine the main stream and deflected vstray stream in a single path.

2. An air propelling device, comprising a rotatable blower having vanes creating a current .of vair composed of several components, one a main stream, and another a radial direction, a fixed casing surrounding said Y the vanes and .enlarged toward thek outlet side ofthe vanes to relieve the choking'ei'e'ctrect said stray stream .into substantiallyfthe same path as the -main stream, and means for confining the two streams thereafter inA a sin le path. f

air propelling device, comprising a rotatable blower having vanes constructed to create a current of air having several components angularly related to each other, and a fixed casing of generally cylindrical form surrounding said vanes providing an inlet opening of substantially the same diameter as that of the vanes and providing an outlet of larger diameter, the said vanes extending axially into said enlarged outlet. l

4. An air propelling device,` comprising a rotatable blower having vanes constructed to create a current of air having several components, one of said components traveling substantially parallel to the axis of rotation of the vanes and the other of'sa'id components traveling in a generally radial -direction with respect to said axis, and-a fixed casing of generally cylindrical contour sur\ rounding said vanes providing an inlet opening of substantially the same diameter as that of the vanes and providing an outlet of larger diameter, the said vanes extendv -ing into said enlarged outlet. of the stray stream on the vanes and to'jdif. j

15. In apparatus of the class described, a blower casing of generally cylindrical con- 'tour having `la mouth of reduced internal diameter, with the interior of said casing ex.

panding to a larger diameter beyond Asaid vrmouth, and a rotatable blower disposed in'Y said casing, with its vanes closely fitting the mouth thereof, and projecting` longitudinally thereof past the point of expansion;

6. ln apparatus of the class described, a blower caslng 0f generally cylindrical contour having a mouth of reduced internal diameter, with the interior of said casing .expanding to a larger diameter beyond said mouth, and a rotatable blower disposed in said casing, withits vanes closely fitting the mouth thereof, and projecting longitudinally thereof past the point of expansion, the casing bein formed with a deflecting surface at sai point of expansion. Dated this twelfth day of September,

FRANS H. C. COPPUS. Witnesses:

` NELLIE'WHALEN,

Gmo. H. KENNEDY, Jr'. 

